Differnece between Iterators and Pointers:

 Differnece between Iterators and Pointers:

Iterators and pointers are similar in that we can dereference them to get a value. However, there are key differences as follows:


POINTERS ITERATORS

  1.  

A pointer hold an address in memory.

An iterator may hold a pointer, but it may be something much more complex. For example, an iterator can iterate over data that’s on file system, spread across many machines, or generated locally in a programmatic fashion.

A good example is an iterator over linked list, the iterator will move through elements that are at nodes in the list whose addresses in RAM may be scattered.


2.

We can perform simple arithmetic on pointers like increment, decrement, add an integer etc. Not all iterators allow these operations, e.g., we cannot decrement a forward-iterator, or add an integer to a nonrandom-access iterator.

   A pointer of type T* can point to any type T object.


An iterator is more restricted, e.g., a vector::iterator can only refer to doubles that are inside a vector container.


3.

We can delete a pointer using delete

Since an iterator refers to objects in a container, unlike pointers, there’s no concept of delete for an iterator. (The container is responsible for memory management.)

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